Gooey Chocolate Sheet Cake

Easy to make, and with a great chocolate flavor, this cake is amazing! The top layer remains gooey and rather soft, so I prefer to serve the cake directly from the pan. I love it slightly underbaked for a fudgier experience. 

Originally posted in August 2012, this post has been updated with images, text, and video to serve you better. The recipe remains the same because it's amazing!

I think this is one of the most playful chocolate cakes ever. So we eat it regularly haha!

It appeals to everyone, comes together really quickly, and has that magic ingredient that is condensed milk. Really people, what recipe isn't great that has condensed milk? I dare you. I can give enough proof with the Margarita Key Lime Pie, the best chocolate fudge EVER, and my favorite Sweet Potato Pie. The proof is in the pudding, definitively.

The frosting alone can be eaten with a spoon, that's how addictive it is. 

So let's get on with the recipe. 

Main ingredients

The list is simple and most you probably have at home right now. If not all. I keep cocoa powder and condensed milk in my pantry at all times. As usual, the best quality ingredients give the best results. 

Cocoa powder - look for the best you can find. It makes a difference. 

• Condensed milk - use the regular kind, any good brand works. 
• Brown sugar - it makes a subtle difference in flavor and moistness, but you can use regular white sugar if that's all you have. 
• Flavorings - vanilla extract (natural) is much better than an essence (which is artificial). I love paste, but any type works. The cinnamon adds depth to the overall flavor, but you can omit it. Also, you can use almond or coffee extract, they go very well with the rest of the ingredients. 

The frosting

This is what makes or breaks a chocolate sheet cake IMO. 

The frosting or icing should be sweet, crackly, and with enough chocolate flavor. This one checks all the boxes, of course. That's why we love it so much. 

Variation: you can add some chopped walnuts after you pour it over the hot cake. 

The process is very easy as you can see in the video tutorial below 👇🏻

1

Mix cocoa powder with melted butter until smooth

2

Add condensed milk and integrate very well

3

Add powdered sugar

4

Mix well until no lumps remain

5

It should be a smooth and creamy mixture

6

Pour over the hot cake and allow to set

Check out my other content @VintageKitchenNotes on Jumprope.

Top tips

• Cake pan: I use a rectangular pan without a removable bottom. This is because when you pour the frosting some of it goes to the sides. If it had a removable bottom it would probably seep through it. 
• Variation - you can make a poke cake, piercing the surface when the cake comes out of the oven with a brochette stick or similar. When you pour the chocolate icing some of it will seep into it making the cake moister. 
• Fudgier cake: if you slightly underbake the cake it will be fudgier. And it will be even more amazing!
• Walnuts: sometimes I sprinkle chopped walnuts on top of the icing before it sets. 

This is the perfect cake to make and snack on it during the weekend, to bake when you have kids and teenagers at home, to take to a barbecue or potluck. 

It keeps well for several days and it's a crowd-pleaser like you wouldn't believe it. Or maybe you would if you made it all the way down here. 

For a sophisticated variation, you can add a tablespoon of your favorite liquor (I love Kahlua, Baileys, and Cointreau) to the batter and the icing. Or whisky, it works so well with chocolate. Did I tell you about my favorite cake in the world, the Bourbon Hot Chocolate Bundt Cake? It's beyond amazing. 

Other chocolate cake recipes you might like:

Flourless Chocolate Almond Cake
The Best Chocolate Bundt Cake
Chocolate Potato Cake

Gooey Chocolate Sheet Cake

★★★★★ 5 from 1 reviews

• Author: Paula Montenegro
• Prep Time: 20
• Cook Time: 20
• Total Time: 40 minutes
• Yield: 12 servings 1x
• Category: Cakes
• Method: Baking
• Cuisine: American

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Description

Easy to make, and with a great chocolate flavor, this cake is amazing! The top layer remains gooey and rather soft,  so I prefer to serve the cake directly from the pan.

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Ingredients

Scale 1x2x3x

For the cake:

• 1 cup butter
• ½ cup cocoa powder, unsweetened
• 1 cup of water
• 2 cups all-purpose or cake flour
• 1 ½ cups firmly packed brown sugar
• 1 teaspoon baking soda
• 1 teaspoon cinnamon
• ½ teaspoon salt
• 1 14-oz can condensed milk, divided 
• 2 eggs, at room t°
• 1 teaspoon vanilla extract

For the frosting:

• ¼ cup butter
• 2 tablespoons cocoa powder, unsweetened
• 1 cup powdered sugar

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Instructions

1. Preheat oven to 350º.
2. Grease a 13x18-inch pan. If you want, you can line the bottom and the two long sides with a piece of foil or parchment.

For the cake:

1. Melt 1 cup butter in a small saucepan.
2. Add cocoa and water and bring to a boil. Remove from heat.
3. In a large bowl mix flour, brown sugar, baking soda, cinnamon, and salt.
4. Make a well in the center and add cocoa mixture, ⅓ can (eyeball it) of the condensed milk, eggs and vanilla. Mix until the batter is smooth.
5. Pour into prepared pan and bake for about 15 to 20 minutes, until cake springs back. Don't overbake it.

For the frosting:

1. In a small saucepan (I use the same one without cleaning it) melt the remaining ¼ cup butter.
2. Remove from heat and add 2 tablespoons cocoa, and the rest of the condensed milk. Mix well.
3. Add powdered sugar and mix until smooth.
4. Spread over warm chocolate cake. Let cool completely.
5. If adding some chopped walnuts do so before the frosting cools and develops the top crust.

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Notes

• Cake pan: I use a rectangular pan without a removable bottom. This is because when you pour the frosting some of it goes to the sides. If it had a removable bottom it would probably seep through it.
• Variation - you can make a poke cake, piercing the surface when the cake comes out of the oven with a brochette stick or similar. When you pour the chocolate icing some of it will seep into it making the cake moister.
• Fudgier cake: if you slightly underbake the cake it will be fudgier. And it will be even more amazing!
• Walnuts: sometimes I sprinkle chopped walnuts on top of the icing before it sets.

Keywords: chocolate sheet cake

Paula Montenegro

I'm Paula, a baker for more than 30 years and your designated recipe finder, sharing the best ones on this blog, with simple ingredients + easy-to-follow instructions.